1. Field
Some example embodiments may relate generally to ultrasonic transducer modules. Some example embodiments may relate generally to ultrasonic transducers. Some example embodiments may relate generally to methods of manufacturing the ultrasonic transducers.
2. Description of Related Art
Ultrasonic transducers such as micromachined ultrasonic transducers (MUTs) may convert electrical signals into ultrasound signals and vice versa. MUTs may be used in diagnostic medical imaging equipment to non-invasively obtain pictures or images of organs or tissues in a human body. MUTs may be classified into piezoelectric MUTs (pMUTs), capacitive MUTs (cMUTs), and magnetic MUTs (mMUTs) according to the conversion methods they use. Among the MUTs, the cMUTs may be mostly used.
A cMUT may transmit and receive ultrasound waves by using a displacement difference between hundreds or thousands of micromachined diaphragms. The cMUT may include a thin film on a silicon (Si) wafer used in a general semiconductor process, wherein a cavity is formed between the Si wafer and the thin film. The Si wafer, the thin film, and the cavity may form a capacitor. When an alternating current (AC) flows through the capacitor, the thin film may vibrate, and the vibration may generate ultrasonic waves. Accordingly, a patient's status may be safely and precisely observed based on the vibration of the cMUT's thin film.